Question

In python, is there a difference between calling clear() and assigning {} to a dictionary? If yes, what is it? Example:

d = {'stuff':'things'} d.clear()   #this way d = {}      #vs this way 

Answer 1

If you have another variable also referring to the same dictionary, there is a big difference:

>>> d = {'stuff': 'things'} >>> d2 = d >>> d = {} >>> d2 {'stuff': 'things'} >>> d = {'stuff': 'things'} >>> d2 = d >>> d.clear() >>> d2 {} 

This is because assigning d = {} creates a new, empty dictionary and assigns it to the d variable. This leaves d2 pointing at the old dictionary with items still in it. However, d.clear() clears the same dictionary that d and d2 both point at.